p–ISSN: 2723 - 6609 e-ISSN: 2745-5254
Vol. 5, No. 9 September 2024 http://jist.publikasiindonesia.id/
Jurnal Indonesia Sosial Teknologi, Vol. 5, No. 9, September 2024 3676
Designing Welding Workstations to Reduce the Risk of MSDS
(Musculoskeletal Disorders)
Machdian Muharam
1*
, Maya Arlini puspasari
2
Universitas Indonesia, Indonesia
Email:
[email protected]
*Correspondence
ABSTRACT
Keywords: ergonomics,
workstation welding,
musculoskeletal disorders,
rule.
This study aims to design an ergonomic welding workstation
to reduce the risk of Musculoskeletal Disorders (MSDs) in
welding workers at PT. Sinar Bharata Perkasa. The
background of this study is the high prevalence of MSDs in
welding workers due to unergonomic work posture. The
methods used include posture analysis using Rapid Upper
Limb Assessment (RULA) and Rapid Entire Body
Assessment (REBA), as well as anthropometric calculations
to design workstations that suit the physical condition of
workers. Data collection was carried out through the Nordic
Body Map (NBM) questionnaire and posture measurements
before and after the design improvement. The results showed
that the new workstation design was able to significantly
reduce the risk of MSDs, with a decrease in the RULA score
from 6 to 3 and the REBA score from 8 to 3. In conclusion,
this new workstation design has the potential to improve the
health and productivity of welding workers at PT. Sinar
Bharata Perkasa.
Introduction
Welding is a way to connect two pieces of metal or more, both ferrous and non-
ferrous, with the process of melting the parent metal and/or filler metal to produce a
continuous connection with or without the use of pressure (Yuslistyari & Adhadin, 2018),
In welding operations, the physical dimensions of the workstation have a significant
influence from the point of view of production efficiency and the physical and mental
well-being of the operator (Anthony, 2020). Physical dimensions in industrial workstation
design are essential for the perspective of production efficiency and occupational health
and safety (Urgiles et al., 2019). (Mahir, 2023) stated several factors that need to be
considered when analyzing and designing a welding environment including the physical
abilities of the workers, the weight of the welding gun, the design tools, the mechanics of
the body during welding, the type of protective equipment used, the workspace, and the
physical requirements of the job and the job position. This type of work that involves the
Designing Welding Workstations to Reduce the Risk of MSDS (Musculoskeletal Disorders)
Jurnal Indonesia Sosial Teknologi, Vol. 5, No. 9, September 2024 3677
physical and is carried out in inappropriate ways, let alone repeatedly, can slowly cause
musculoskeletal disorders. This needs to be taken seriously, as it can lead to more severe
consequences. Since there is a strong association between other occupational risk factors
and work posture, there is a need to assess how they intend to increase productivity
(Thoriq & Sutejo, 2017). The prevalence of MSD disorders according to the World Health
Organization (WHO) reaches around 60% of all occupational diseases (Saraswati, 2020).
Meanwhile, data from the Labour Force Survey (LFS) in 2017 shows that
Musculoskeletal Disorders (MSDs) in the last 3 years are ranked second out of all cases
of occupational accidents and diseases reaching 469,000 cases (prevalence of 34.54%)
(Mulyadi & Iswanto, 2020). In Indonesia, data on MSDs statistically with details are not
yet available. However, based on Riskesdas data in 2018, there were 9.2% of injuries
resulted in disruption of daily activities in Indonesia, and 9.1% occurred in the workplace
environment. The tendency of joint diseases in the population or workforce over 15 years
old in Indonesia is around 7.3%. However, data (figure 1) from BPJS Kesehatan shows
that the cost of health services sourced from occupational diseases shows a fairly high
intensity every year. This shows that it is quite serious for the handling of prevention
(Shufiyah, 2018).
There have been previous studies that have reviewed the design of workstations for
welding areas. The process of designing this workstation involves the application of the
DFMA or Design for Manufacture and Assembly method and the assembly method
selection diagram. (Dahda & Rizqi, 2022). The result of the workstation design includes
a workbench equipped with a footrest to make it easier for the operator to rest, a place for
a protractor, a welding wire container, a workpiece base plane, and an area for placing
the material to be welded. There are also clamps in the form of a vise with a height of 73
cm, a length of 60 cm, and a width of 60 cm. (Anwardi et al., 2019), while Hilman (Fauzi
& Khusuma, 2020) Made a design for this ergonomic workstation including a table with
a height of 112 cm, a length of 200 cm, and a width of 75 cm, this was developed to
reduce muscle fatigue and discomfort in the workplace and the height of the table is 5-10
cm above the height of the worker's elbow when standing.
Many studies have studied the design of workstations in the welding area. Some
focus on risk analysis and posture evaluation. The object of the research is a welding area
workstation in a company in the city of Bekasi, West Java.
However, comprehensive research that integrates all aspects, including posture
analysis, anthropometry, productivity, cost, design visualization, layout, and welding
workstations is still limited. Most previous studies have only evaluated postures or
proposed designs without an approach that considers all relevant factors. In addition,
posture evaluation before and after design improvements using the Nigel Cross model has
not been explored in depth for welding workstations. Therefore, the researcher conducted
research that can be a novelty value, namely by designing a welding workstation that will
be implemented at PT. Sinar Bharata Perkasa. The results of the research are in the form
of design and visualization which will be designed based on posture analysis of existing
work activities. The existing design will be designed using the Nigel Cross model whose
Machdian Muharam, Maya Arlini puspasari
Jurnal Indonesia Sosial Teknologi, Vol. 5, No. 9, September 2024 3678
data is primary data in the field. Posture evaluation is carried out before and after design
improvements to evaluate the design results until the final design is produced.
Method
Research Subjects and Data Collection
The subject of the study is a welding operator whose anthropometric data is
secondary data taken from Indonesia's anthropometry. Org (2018)
(www.antropometriindonesia.org). The anthropometric data used in this study are 36
anthropometric dimensions which are measurements, for all ethnicities, males, and
measurement times from 2000 – 2018 with an age range of 17 to 47.
From the existing data, calculations will be carried out by calculating percentiles
for existing dimensions, using the formula (2-1), and the combined standard deviation
will be calculated using the formula (2-2).
This study adapts following the steps used in the rationality model from Nigel Cross
which includes 7 steps of clarification Objective, Establishing Function, Setting
Requirement, Determining Characteristic, General Alternative, Evaluation Alternative,
N1M1+N2M2 N1+ N2 (2-1)
Improving Detail Engineering Design Methods Strategies for Product Design
(Nigel Cross, 2000).
RULA and REBA Measurement
RULA is an approach to evaluate the ergonomics of workers' posture, focusing on
the upper body. RULA analysis is used when there are complaints related to discomfort
in the upper body due to unergonomic work posture (McAtamney and Corlett, 1993). The
advantage of this method lies in its ease of use as it does not require special equipment.
Factors to consider in the analysis include the position of the body when in a static state
when working, load, duration, and use of muscle energy in working.
REBA is a systematic method used to evaluate the body position of all workers to
identify the risk of Musculoskeletal Disorders (MSDs) and other related occupational
risks (Ergonomics Plus, n, d.). REBA was first introduced by Hignett and McAtamney
(Hignett et al, 2000). A REBA sheet is used to assess energy use, posture, type of
movement, coupling, and repetition. REBA was developed to be easy to use without the
need for high skills or expensive equipment. In its use, REBA only requires REBA sheets
and stationery.
From the results of RULA and REBA, a value with a risk level for MSDs was
obtained.
Designing Welding Workstations to Reduce the Risk of MSDS (Musculoskeletal Disorders)
Jurnal Indonesia Sosial Teknologi, Vol. 5, No. 9, September 2024 3679
Figure 1. Research flow
The research flow adapted from these 7 steps is only limited to the Evaluation
alternatives phase, that is, the seventh phase, namely Improving details is not carried out
in this study. The reason this research only adapts the initial 6 phases is because this
research is only limited to the stage of producing improvement designs, not considering
the production process and the release process to the market.
1) Clarifying Objective
The first phase begins with a preliminary study, exploring the basic information of
potential subjects, compiling the background of why this research is conducted,
formulating problems obtained from information in the field, determining the limitations
in conducting this research, and preparing a research plan, starting from how this research
will be conducted, what data is needed, how the stages of the research process are carried
out until the final output.
The steps are as follows:
a. Compile a list of design goals by summarizing information based on questions to users,
design reports, and design team discussions.
b. Preparation of a list of goals from higher level to lower level. From this process comes
a list of goals and sub-objectives that are roughly grouped into hierarchical levels.
c. Compile a goal tree diagram, as a visualization of existing relationships.
2) Penetapan Fungsi (Establishing Function)
This stage has the purpose of identifying the functions that occur in a design. This
step involves drawing system constraints that include the functions and sub-sub-functions
of the planned tool, transparent box, and black box.
3) Setting Requirements
Compile a table that contains details of the specifications of the tool based on the
data obtained from the questionnaire. The detailed table of specifications includes the
requirements that need to be met (demand) and things expected (wishes) by respondents.
4) Determining Characteristic
The determination of product characteristics aims to identify the targets to be
achieved through the technical characteristics of a product, to meet the needs of
respondents. The opinions of other stakeholders were determined, and respondents were
given a questionnaire about several alternative options.
5) Evaluating alternatives
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Jurnal Indonesia Sosial Teknologi, Vol. 5, No. 9, September 2024 3680
In this stage, a questionnaire containing several alternative designs of the new tool
was distributed to respondents. Respondents were asked to choose one of several options
provided to identify one alternative option. The chosen alternative will be the basis for
designing a new welding workstation.
6) Communication (improving details)
The components of the new device are described in detail, to make modifications
to add value without adding or reducing costs and still maintaining the existing value.
Market surveys are conducted to find out the price of each component. After knowing the
price of the components, an evaluation is carried out on the modification of the device.
However, cost calculations were not included in this study.
Statistical Calculation of Questionnaire Data
This study uses 2 types of questionnaire calculations statistically as follows:
a. Validity Test
Validity testing was carried out to evaluate the accuracy of the data
collection instruments that had been used by utilizing data from closed questionnaires. It
can be seen in equations 2-3.
b. Reliability Test
In this stage, alternatives are determined by compiling a morphological chart that
includes functions and ways of achieving them. These alternatives are based on the results
of a questionnaire given to respondents and interviews with experts. Based on
alternatives.
Reliability testing is carried out after the data is confirmed as valid data to evaluate
the measurement results. Reliability testing uses the same software as the validity test,
namely SPSS software. It can be seen in equations 2-4.
Results and Discussion
Literature Studies and Design
Literature studies are carried out on previous studies. A literature study was
conducted for the selection of anthropometric dimensions and appropriate designs for use
in determining dimensions for tables and chairs in welding workstations.
Based on the activities carried out by workers at PT. X will be calculated RULA
(Rapid Upper Limp Assessment) and REBA (Rapid Entire Body Assessment) from the
measurements shown below.
Designing Welding Workstations to Reduce the Risk of MSDS (Musculoskeletal Disorders)
Jurnal Indonesia Sosial Teknologi, Vol. 5, No. 9, September 2024 3681
Figure 2 Worker standing position
Figure 3 Worker RULA standing
While REBA is as follows:
Figure 4 REBA worker standing position
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Jurnal Indonesia Sosial Teknologi, Vol. 5, No. 9, September 2024 3682
Figure 5 Worker sitting position
While RULA with a sitting position:
Figure 6 Worker RULA in a seated position
Designing Welding Workstations to Reduce the Risk of MSDS (Musculoskeletal Disorders)
Jurnal Indonesia Sosial Teknologi, Vol. 5, No. 9, September 2024 3683
As for REBA with a sitting position:
Figure 7 REBA worker in a seated position
From the data above, it turns out that the RULA and REBA values for the condition
of workers without desks are 6 and 8, so with these values, the condition of workers has
a high enough risk to be affected by MSDs and it is necessary to investigate and
implement improvements as soon as possible. As for workers using the value table
Kuesioner Nordic Body Map (NBM).
RULA and REBA range from 5 and 6 which means that workers using existing
tables are still exposed to the risk of MSDs even though the risk is medium, so it is
necessary to reduce the above values by improving the design to further reduce the risk
of MSDS for workers in the welding area.
In identifying the complaints experienced by operators, the researcher conducted a
questionnaire using the Nordic Body Map (NBM), from the results of the questionnaire
the following data was obtained:
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Jurnal Indonesia Sosial Teknologi, Vol. 5, No. 9, September 2024 3684
Figure 8 Nordic Body Map Questionnaire (NBM)
From the data obtained, weighting was carried out with a Linkert scale from scale
1 to 4, namely so that data on pain in the right shoulder, right upper arm, and waist
dominated the workers' complaints.
Figure 9 Recap of the Nordic Body Map (NBM) Questionnaire
Anthropometric Calculations
Calculations of 5th, 50th, and 95th percentile values are carried out for each
dimension based on the average value and standard deviation. The calculation of
percentile values is carried out by adding the average value with the result of
Designing Welding Workstations to Reduce the Risk of MSDS (Musculoskeletal Disorders)
Jurnal Indonesia Sosial Teknologi, Vol. 5, No. 9, September 2024 3685
multiplication between the standard deviation and the multiplier factor according to the
required percentile. In this study, the multiplier factor used was -1.645 for the calculation
of the 5th percentile, the multiplier factor of 0 for the 50th percentile, and the multiplier
factor of 1.645 for the calculation of the 95th percentile. For example, for the height
dimension of the body, the average value is 148.18 cm with a standard deviation of 1.9
cm, then the calculation of the percentile is 5, 50, and 95:
𝑵𝒊𝒍𝒂𝒊 𝑷𝒆𝒓𝒔𝒆𝒏𝒕𝒊𝒍 𝟓 (𝑫𝟏) = 𝑀𝑒𝑎𝑛 − 1,645 × 𝑆𝑡𝑑𝑒𝑣
= 148,18 − 1,645 × 15,66
= 122,42
𝑵𝒊𝒍𝒂𝒊 𝑷𝒆𝒓𝒔𝒆𝒏𝒕𝒊𝒍 𝟓𝟎 (𝑫𝟏) = 𝑀𝑒𝑎𝑛 + 0 × 𝑆𝑡𝑑𝑒𝑣
= 148,18 + 0 × 15,66
= 148,18
𝑵𝒊𝒍𝒂𝒊 𝑷𝒆𝒓𝒔𝒆𝒏𝒕𝒊𝒍 𝟗𝟓 (𝑫𝟏) = 𝑀𝑒𝑎𝑛 + 1,645 × 𝑆𝑡𝑑𝑒𝑣
= 148,18 + 1,645 × 15,66
= 173,94
Thus, it was found that the magnitude of the 5th percentile value for the height
dimension of the body (D1) was 122.42 cm, the 50th percentile was 14.18 cm and the
95th percentile was 173.94 cm. The results of the calculation of percentile values for each
dimension are illustrated in Table 1.
Table 1
5thrants, 50, and 95 Percentile Values Each
D14
36,27
45,80
55,33
D15
42,28
52,42
62,56
D16
33,02
42,00
50,97
D17
27,67
40,91
54,15
D18
22,14
33,14
44,15
D19
30,48
43,45
56,43
D20
11,14
22,89
34,64
D21
12,63
28,34
44,06
D22
21,91
29,81
37,71
D23
27,83
38,60
49,36
D24
55,32
66,48
77,64
D25
39,82
49,69
59,57
D26
12,61
18,11
23,61
D27
13,60
20,50
27,40
D28
10,97
17,41
23,85
D29
6,77
10,55
14,33
D30
16,87
22,64
28,41
D31
7,61
10,84
14,08
D32
116,7
6
144,00
171,2
3
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Jurnal Indonesia Sosial Teknologi, Vol. 5, No. 9, September 2024 3686
D33
59,81
72,80
85,79
D34
145,2
0
188,23
231,2
7
D35
87,79
123,14
158,5
0
Validity and Reliability Test
1. Validity Test (moved up)
From the 30 available data to assess the level of desire of respondents for welding
workstations. Validity tests were conducted to evaluate the extent to which the questions
presented in the questionnaire could reflect the overall behavior of the respondents. The
results of the Validity Test were carried out using SPSS for r table 5% for N =30 and the
results are as shown in table 2.
Table 2
Validity Test Scores
No.
Grain
r Table
Information
1
0,361
Vali
d
2
0,361
Vali
d
3
0,361
Vali
d
4
0,361
Vali
d
5
0,361
Vali
d
6
0,361
Vali
d
7
0,361
Vali
d
8
0,361
Vali
d
9
0,361
Valid
2. Reliability Test
For the existing data, a reliability test is carried out to determine the uniformity of
the data, by calculating the value of Alpha Cronbach. The results of this test can be seen
in Table 8 below, from the existing data, the value of r Calculate is greater than r Table
so it can be concluded that the existing data is reliable.
Table 3
Reliability Test Score
Attribut
e
r
Calcula
te
r
Table
Informati
on
Cronbac
0,832
0,361
Reliable
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Jurnal Indonesia Sosial Teknologi, Vol. 5, No. 9, September 2024 3687
h's
Alpha
Nigel Cross design model
The design guidelines of the welding workstation are made based on the
anthropometric considerations of the operator as the user and the improvement effect of
the design before and after it is carried out. In the preparation of this design, it is carried
out by reference following the 7 steps in the design model, the results of these steps are
as follows:
3. Clarifying Objective
Creating a goal setting by creating an objection tree which is the result of digging
for input/ideas from users, can be described as follows:
Figure 10. Destination Tree
a. Establishing Function creates a black box that aims to determine the process that will
be carried out to determine that the welding workstation can be implemented
into a product. For the black box which is described as a process flow for the
manufacture of welding workstations.
b. Preparing Requirements (setting requirements) Contains a table that is the need for a
product to be designed, this table contains requirements that are by the wishes (D) and
expectations (W) of users from welding workstations based on questionnaires at PT.
Sinar Bharata Perkasa.
Table 4
Setting requirement
D or W
Cond
ition
W
Square table
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Jurnal Indonesia Sosial Teknologi, Vol. 5, No. 9, September 2024 3688
W
Dimensions: 2000 x 1200 x
500-600 mm
W
Black table
W
Table with Steel material
D
Table with 5-inch wheels
D
Has a durability of 5 years
W
Table Power up to 200 Kg
W
Main functions of the
workbench
W
Functional table support jig
c. Determining Characteristic
In this step, QFD (Quality Function Deployment) is prepared, the goal is to find
characteristics to suit customer requests by prioritizing the design quality of the product
compared to existing competitors so that the product can be made based on requests from
users/users. The existing characteristics are expected to be able to adjust their desires by
exploring the expectations of users.
d. Determining alternatives
At this stage, a morphological chart was developed to see the alternatives to welding
workstations as follows.
Figure 11 Morphological chart
Table 5
Attribute Weighting Table
Value
scale
Functi
on
Description of sub-
functions
In
10
D
Table/tool height
10/52=19,23%
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Jurnal Indonesia Sosial Teknologi, Vol. 5, No. 9, September 2024 3689
9
A
Table size
9/52=17,31%
8
G
Using the wheel
8/52=15,38%
7
C
Tool power
7/52=13,46%
6
B
Frame Material
6/52=11,54%
5
And
Swivel table
5/52=9,62%
4
H
Storage Rack
4/52=7,69%
3
F
Heat sucker
3/52=5,77%
2
-
-
1
-
From the existing morphological chart, there are 3 alternatives with 9 attributes so
from the data above there are 39 alternatives, totaling 19,683 alternatives which will then
be carried out in the alternative evaluation stage by looking at the weighting of existing
attributes to others, for this a questionnaire will be carried out to see the response from
users to the existing alternatives.
e. In this phase, several welding workstation design alternatives that have been produced
will be evaluated, and one of the two best options will be selected, this selection aims
to ensure that the workstation design can produce the best product among the several
alternatives available. So that the design for the welding workstation table is carried
out based on the existing anthropometric needs, and at this stage, a simulation will also
be carried out using Siemens Jack software to see the posture analysis of the existing
design.
f. Communication (improving details)
At this stage, design is carried out by choosing alternatives that have been
determined, taking into account anthropometric factors that have been taken into account
beforehand. In addition, the next value engineering will also be considered for the design
of the resulting product.
In value engineering, all the parts and components needed will be listed so that the
value of the product produced can be calculated.
Conclusion
This study aims to design an ergonomic welding workstation to reduce the risk of
musculoskeletal disorders (MSDs) in welding workers at PT. Sinar Bharata Perkasa. The
calculation of RULA and REBA scores shows that the current working conditions have
a fairly high risk of MSDs for workers, both when working without a desk and with
existing desk conditions. The Nordic Body Map questionnaire revealed that the main
complaints of workers were in the right shoulder area, right upper arm, and waist. The
design of the new welding workstation table is carried out by considering the
anthropometric data of the worker, including the dimensions of body height, sitting
shoulder height, upper arm length, and so on. In addition, the purpose, functions, needs,
and characteristics of the workstation are also determined based on input from users
through questionnaires. Alternative workstation designs are generated with
morphological charts and an evaluation process using Quality Function Deployment
(QFD). The selected alternatives were then designed in detail taking into account
Machdian Muharam, Maya Arlini puspasari
Jurnal Indonesia Sosial Teknologi, Vol. 5, No. 9, September 2024 3690
ergonomic factors and simulated working postures using Siemens Jack software. Before
the design of the RULA value in the standing and sitting positions was 6 and 5, and for
REBA it was 8 and 6, after the design of the RULA value obtained from the simulation
results with the jack software, there was an improvement in the standing and sitting
position with a value of 3 so that the design of the existing workstation table could reduce
the risk of MSDs (Musculoskeletal Disorder) of welding workers at PT. Sinar Bharata
Perkasa.
The theoretical implications of this study are in the form of new contributions to
the application of ergonomic principles in the design of workstations in the manufacturing
industry, especially for welding work. The study combines various analytical methods
such as RULA, REBA, anthropometry, QFD, and simulation in one systematic product
design framework. The findings of the study can enrich the literature related to the design
of welding workstations that are safe and comfortable for workers.
The practical implications of the new workstation design research resulting from
this research have the potential to be applied in PT. Sinar Bharata Perkasa to reduce the
risk of MSDs to welding workers. This design can also be adapted for use in other
companies that have similar welding activities. This research has several limitations. The
research was only conducted at PT. Sinar Bharata Perkasa with a limited sample number
of workers. In addition, similar studies need to be conducted on other industries taking
into account specific factors such as the type of work, environmental conditions, and
worker characteristics to obtain a broader generalization. Future research may explore
other MSD mitigation efforts such as job rotation, posture training, and management
interventions.
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Jurnal Indonesia Sosial Teknologi, Vol. 5, No. 9, September 2024 3691
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